Pioneer A06 with Ulead DVD player--doesn't work anymore

Hi:
I use windows 98se. I've always used the windows media player
(6.4) to play avi's and mpg's.
I recently bought a Pioneer A06 that comes with Ulead DVD player
software.
I installed it, and it played several DVD's I own with no
problem.
Then I used media player to watch some videos, and when I
returned to the pioneer, it would no longer play any dvd's.
I contacted Ulead and they said to uninstall the dvd player and
reinstall it.
I knew that probably wouldn't work, but I did it anyways.

I was right. It still wouldn't play dvd's.

I don't understand much of the technical stuff about video,
codecs, etc. But what little I do know tells me that some
associations or files got changed, or deleted. Probably some registry
changes as well.

Maybe this is a stupid question, but why can't the software
companies agree on some standards, so that different software won't
interfere or conflict with each other.
Or at least, why can't all software installations create a
detailed log of what they do, what files they add, change, or delete,
and what registry changes they make.

This REALLY bugs me. I have NO idea what to do to get this
pioneer burner to start playing dvd's again. It cost me a lot of
money, and now I can't use it because damned Ulead , Microslut, maybe
ATI (my video card) can't work together in harmony.

By the way, I called Ulead and they told me to do a clean install
of Win98se and reload all my programs. I said F*** you and slammed
the phone down. Their problem......and they want me to do the
near impossible job of hours and hours and hours of reloading and
reconfiguring programs. (And when I was all done, the same problem
would probably happen again.)

Why, why, why can't they just make software that lets the user know
what changes are being make to settings, configurations, etc. And the
damned registry is so cryptic that most people would have no idea
where to look in it to fix problems.

I think the **** software companies like to screw us on purpose.


Anyways, sorry for the rant. I'm just very upset, not only at the
problem but also at the response/attitude of Ulead.

Does any computer guru out there have any suggestions on what I
could do to fix this?

Thank you.

abc